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<!-- * $Date: 2003/06/26 01:13:58 $                                   -->
<!-- * $Author: dietrick $                                            -->
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<body>

The GraphicLoader PlugIn package is designed to provide support for
GraphicLoaders, which in turn are objects that need to drive changes in
OMGraphics over a map.  The GraphicLoader is an object that manages
OMGraphics and their positions, and sends an OMGraphicList to its
receiver when they need to be updated. <P>

The package consists of a GraphicLoaderPlugIn, which is a PlugIn that accepts
graphics from another object, called the GraphicLoader.  The GraphicLoader
is an object with a timer that manages these location objects. The
GraphicLoaderConnector is an object that should be added to the
MapHander - when it finds a GraphicLoader in the MapHandler, it will
automatically create a GraphicLoaderPlugIn for it, and
will either give the GraphicLoaderPlugIn to the LayerHandler if it
knows about one, or give the GraphicLoaderPlugIn to the MapHandler so
it can be found by the LayerHandler later.<P>

To add a GraphicLoader to the OpenMap application, you can do it
several ways:
<UL>
<LI>You can create a specific GraphicLoaderPlugIn that creates its
  own GraphicLoader, and initializes it accordingly.  You would add
  the GraphicLoaderPlugIn to the openmap.layers property in the
  openmap.properties file.
<LI>You can create a GraphicLoaderPlugIn by adding an entry to the
  openmap.layer property in the openmap.properties file, and define
  what kind of GraphicLoader to create in the properties for the
  GraphicLoaderPlugIn.
<LI>You can add a
  com.bbn.openmap.plugin.graphicLoader.GraphicLoaderConnector to the
  openmap.components property, and then add the GraphicLoader to the
  openmap.components property as well.  The GraphicLoaderConnector
  will find the GraphicLoader, and create a
  GraphicLoaderPlugIn/PlugInLayer for the GraphicLoader and add it to
  the LayerHandler on top of the map.
</UL>
</body>
